1. Field of the Invention
The present invention relates to a semiconductor device and a manufacturing method thereof.
2. Description of Related Art
Recent development in technology has brought practical application of stacking type semiconductor devices designed to be stacked one on another. For example, a related stacking semiconductor device employs a structure in which a semiconductor chip is sealed with resin or the like and external terminals used for stacking are provided in the outer periphery thereof.
A related stacking semiconductor device is typically composed of a wiring board for mounting a semiconductor chip, wires of Au or the like for electrically connecting between the wiring board and the semiconductor chip, resin for protecting the semiconductor chip from the outside, solder balls for external connection, and external terminals used for stacking. The external terminals used for stacking are arranged in the outer periphery of the sealing body made of resin or the like, which poses a restriction for the arrangement of the external terminals that the sealed region must be avoided.
The related stacking semiconductor device is typically manufactured by a method as described below.
Firstly, a semiconductor chip is mounted on a wiring board, and the wiring board and the semiconductor chip are connected to each other by means of wires of Au or the like. The semiconductor chip is sealed with resin while avoiding external terminals provided on the surface on which the semiconductor chip is mounted and required for stacking another semiconductor device. Finally, solder balls are mounted, and the board is cut to obtain a stacking semiconductor device.
A related stacking semiconductor device fabricated in this manner has a structure in which a semiconductor chip is fixed to the top of a wiring board, electrodes of the semiconductor chip and wiring lines on the top surface of the wiring board are connected to each other by means of wires, and the wiring board has electrodes on the lower surface thereof. The semiconductor chip and the wires on the top surface of the wiring board are covered with a sealing body made of an insulative resin. Connection lands for a semiconductor device to be stacked on top of this semiconductor device are provided on the top surface of the wiring board in the outside of the sealing body.
A related semiconductor device is described for example in Japanese Laid-Open Patent Publication No. 2006-303079.
In the related stacking semiconductor device, however, the connection lands for connection of a semiconductor device to be stacked on top thereof are provided in a region outside the sealing body of the wiring board. This poses restrictions on the arrangement and size of external terminals of the semiconductor device to be stacked on top. The restrictions posed on the external terminals include, for example, the need of arranging the external terminals in a fan-out pattern, and the need of designing the external terminals to be higher than the height of the sealing body. These restrictions impair the degree of freedom in designing the external terminals of the semiconductor device to be stacked on top.
The fan-out pattern arrangement of the external terminals in the semiconductor device stacked on top leads to increase of the area of the wiring board used for each semiconductor device, which may lead to increase in the manufacturing cost of the semiconductor device stacked on top.
Moreover, if the diameter of the external terminals of the semiconductor device stacked on top is increased in order to make the external terminals higher than the height of the sealing body, it will also increase the dimension in planar direction and will cause a problem of increased distance between the lands. If an intermediate member is used to add its height to the height of the external terminals, it will increase the manufacturing cost.
Other related semiconductor devices are described for example in Japanese Patent Publication No. 2004-327855 and No. 2004-56093.